Not an artificial note (7)
I believe the answer is:
natural
'note' is the definition.
(I've seen this before)
'not an artificial' is the wordplay.
I cannot quite understand how this works, but
'an' could be 'a' and 'a' is found in the answer.
'not' could be 'nt' (synonyms) and 'nt' is found within the leftover letters.
The remaining letters 'ural' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for natural that I've seen before include "Not artificial or affected" , "Frank < , twenty-one" , "Normal; not sharp or flat" , "Illegitimate" , "Inborn; unaffected" .)